Optically active polymeric alpha olefins and processes for making same



United States Patent 3,193,544 OPTICALLY AQTIVE PQLYMERIC ALPHA OLE-FINS AND PROCESSES FOR MAKING SAME Giulio Natta, Milan, and Piero Pinoand Gian Paolo Lorenzi, Pisa, Italy, assignors to Montecatini SocietaGenerale per lludustria Mineraria e Chimica, a corporation of Italy NoDrawing. Filed Jan. 15, 1960, Ser. No. 2,607 Claims priority,application Italy, Jan. 15, 1959, 731/59 12 Claims. (Cl. Nil-93.7)

This invention relates to polymeric alpha-olefins which are opticallyactive in solution, and to process for producing them. Moreparticularly, the invention relates to crystallizable polymericalpha-olefins having isotactic structure to amorphous (atactic)non-crystallizable polymeric alpha-olefins, which polymers are opticallyactive in solution, and to processes for producing the same.

The new optically active polymers of our invention can be obtained bypolymerization, under conditions as described below, of optically activealpha-olefins having the general formula CH =CHR in which R is abranched alkyl radical containing 4 to 8 carbon atoms at least one ofwhich is an asymmetric carbon atom, or in which R is an alkylarylradical in which the alkyl portion contains 2 to 8 carbon atoms at leastone of which is an asymmetric carbon atom.

Alternatively, we can obtain new optically active polymers by startingwith optically inactive alpha-olefins such as propylene; butene-l;3-methyl butene-l; styrene, alkyl-styrenes, S-methyl pentene-l, racemic4-methylhexene-l and so on, an polymerizing the same in contact with acatalyst prepared from an optically active organometallic component.

' As is known, the isotactic polymers which have been obtainedpreviously from optically inactive alpha-olefins, do not exhibit opticalactivity in solution. This results from the fact that those knownisotactic polymeric alphaolefins consist of macromolecules which must beregarded as compounds having a meso structure and the low opticalactivity which could be predicted for each of such macromolecules due todiiferences in the end groups is balanced by the optical activity ofopposite sign which is exhibited by other macromolecules present in thepolymers. Th-ose known isotactric polymers behave, in solution, asraeemic substances.

An object of this invention is the new polymeric alpha-olefins, whichmay be isotactic and crystallizable, and which exhibit optical activityin solution.

Another object is to provide methods for producing the optically activepolymers either from optically active alpha-olefins from opticallyinactive alpha-olefins.

Surprisingly, we find that we can obtain polymers which exhibitpronounced optical activity in solution by polym-.

The very high rotary power exhibited by our newpolymers cannot beattributed only to the asymmetrical carbon atoms present in the sidechains. 1

This very pronounced rotatory power exhibited by our polymers can beexplained by assuming that the polymer erized in accordance with ourinvention to polymerizates which exhibit marked optical activity insolution include (S) -3-methyl-pentene- 1 (S)-4-methyl-hexene-1 (S)-5-methyl-heptene-1 -3-phenyl-pentene-l -3-methyl-hexene-1-3-methyl-heptene- 1 -4-phenyl-pentene-1 -3 -phenyl-hexene- 1-4-phenyl-hexene- 1 -5 -phenyl-hexene-1 The Symbol .S in designating theoptically active .com pounds, was proposed by Cahn, Ingold and Prelog(Experientia 1956, 12, 81) and has been already adopted in BellsteinsHandbuch der Organischen Chemie. or other optical antipodes.

We find further, and as a modification of our invention, that we canobtain polymers which exhibit optical activity in solution, fromoptically inactive alpha-olefins, by polymerizing the latter in solutionin contact with catalysts prepared by mixing the transition metalcompounds with optically active organometallic compounds having theformula MeR' where Me is a metal belonging to Groups I to III,inclusive, to the Mendeleefi Periodic Table, n is a whole numbercorresponding to the valence of said metal, and R is a hydrocarbonradical containing at least one asymmetric carbon atom.

In the formula MeR for the optically active organometallic component ofthe catalyst, Me is preferably Li, Mg, Be or Al, and R represents, e.g.,the radical 2- methyl-n-butyl, S-methyl-n-pentyl, S-phenyl-n-pentyl, 4-methyl-n-hexyl, 5-methyl-n-heptyl.

. Among the optically active organometallic compounds which are usefulas one catalyst forming component, we find that (+)-tris-[(S)2-methyl-butyl] aluminum etherate is particularly etiective.

As solvents, for polymerizing the inactive monomers in solution arepreferably used saturated aliphatic or aromatic hydrocarbons.

The optically active polymerizates obtained according to bothmodifications of our invention are mixtures of (1) highly crystallizablemacromolecules the observed data,

for which corresponds to that of macromolecules substantially having anisotactic structure, (2) macromolecules comprising both crystallizableand non-crystallizable chain portions, and (3) amorphous (atactic)noncrystallizable macromolecules, all of which macromolecules exhibitoptical activity in solution.

macromoleculesretain their spiralized form in solution The stericallydifferentiated macromolecules contained in the crude optically activepolymerizates can be separated from each other by fractional dissolutionon the basis of their differences in steric structure. The organicsolvents to be used in such fractionation will vary with the startingmonomer, and for each solvent the amorphous (atactic) macromolecules andthe partially crystallizable macromolecules are more soluble than thehighly crystallizable polymers. The isotactic (crystallizable)macromolecules can be separated by treating the polymerizate withsolvents such as aliphatic ketones or esters, which remove, selectively,the amorphous macromolecules, and

then treating the residue of that treatment with a solvent such as analiphatic ester or ether which dissolves the partially crystallizablemacromolecules, leaving the highly Patented July 6, 1965' desired, bothof those types of macromolecules can be extracted simultaneously bytreating the polymerizate with a solvent for the partiallycrystallizable macromolecules.

It was filtered, the residue was collected and dried on a water bathunder a'pressure of 20 mm. Hg until a constant weight was reached.

Using 6.92 g. of the monomer, and after a polymeriza- The crystallizablepolymers obtained from the optically tion time of 490' minutes, 3.16 g.of thus purified active monomers, and which exhibit optical activity in(+)poly-(8*) 3-methyl-pentene-l were obtained, the consolution, show, ingeneral in the solid state, a much higher version on monomer used being45.7%. crystallinity that the corresponding polymers obtained The crudepolymer was further purified by treating from the racemic monomers andwhich are optically in- 1 it with hydrochloric acid and methanol. activein solution. On the other hand,'the melting points 10 The final polymerobtained was compared with a polyof the two types of polymers (opticallyactive and optimer obtained by starting with racemic 3-methyl-pencallyinactive) are not very different. p tene-l.

We have found that, under thesame polymerization The. polymerization ofracemic 3-methyl-pentene-1 was conditions, the optically activealphaolefins polymerize carried out with the same. procedure asdescribed above. more readily than the racemic olefins. For example, op-2.61 g. polymer Were obtained in a polymerization time crating at roomtemperature, we have obtained polymers or about 515 minutes from 6.68 g.monomer, with a of (S)-4-methyl-hexene-1 with high conversions, whereasconversion of 39.1%. I 1 7 under the same conditions only traces ofpolymer are Table I shows the results obtained by extracting theobtained from the racemic 4-methyl-hexene-1. two different crudepolymers with organicsolvents. The

As a result of the very high crystallinity exhibited by extraction wascarried out in a Kumagawa extractor. our new optically active polymericalpha-olefins in the Tablp I solid state, those polymers areparticularly suitable for the production of self-supporting films andall-purpose textile I v fibers having a very high mechanical strength.Emotions obtained glggagg ggfi ggg g gtgggt The following examples aregiven to illustrate our mmethylpentene-l methyl-pentene-l vention, itbeing understood that these examples are not intended to be limiting.fig g gg g m e g 2-8 7 EXAMPLE 1", V lsoct he extr t, gerce 12:8 7

3.38 g. Al(i=C H previously distilled under vac- 0 3253; iig i ififiififfi 2 2 1?;

uum, were'introduced while stirring into a 100 ml. flask Containing 0.88g. TiCl (obtained by reducing TiCl with 1 The sample shows lowcrystallinity.

H provided with a reflux condenser; the upper end y l of the flask beingconnected, through CaCl -towers, with The polymer fractions thusextracted were isolated by a gasholder filled with pure N 1 The molarratio evaporating'the solvent under reduced pressure and then. A1(i=C H/TiC1 was about 3. V dried on a waterbath'. under a pressure of about 30mm.

The temperature was regulated by an oil bath in which Hg until therespective fractions had a constant weight. the flask was immersedduring the polymerization. All fractions thus obtained were examined fortheir opti- When the preparation of the catalyst was completed, calactivity in decahydronaphthalene solutions with diifer- 6.92 g. of(+)(S)-3-methyl-pentene-l was introduced 40 em dilutions. 1 undernitrogen, into the flask. p i V Similar determinations were also carriedout on poly- Methanol, cooled in coils immersed in an ice-salt remersolutions obtained by heating with decahydronaphfn'gerating mixture, wascirculated in the cooler during thalene the residue after benzeneextraction in an oscilthe polymerization in order to prevent olefinlosses (boillating autoclave (time 14 hours, average temperature ingpoint 54 C.). 280 'C.). This treatment was carried out in order to Thepolymerization was carried out at an average tem'-- decrease themolecular weight of the polymer, thus inperature of 80 C. creasing itssolubility.

As the polwnerization proceeded, the agitation was The apparatus usedfor determining the optical activity more and more hindered until itceased completely; the was a direct-reading Lippichs polarimeter, havinga sensimass was heated until the reflux disappeared and was then 0bility of 0.005". All the fractions of the (+)(S)-3- stopped. Whilestrongly cooling the flask with ice-salt, methyl-pentene-l polymershowed optical activity in solucc. absolute ethyl alcohol were thenadded in small tion as shown in Table II, in which the angles read onportions under nitrogen. the polarimeter, as well as the approximatevalues of The mass was poured into a 1 liter flask where it was specificand molar rotations referred to the molecular refluxed under nitrogenfor some'hours with 200-300 cc. Weight of the monomeric unit, deducedtherefrom, are ethanol. 7 given. All of the measurements reported inTable II At the end of this treatment the polymer waswhite. were carriedout in decahydronaphtha'lene.

Table 11 Polymer not treated with HCl Purified polymer 1 Analyzedfractions 7 I n 0012 I (1/100 m1. [am 1 [M19 G./ ml. 1 1 [04, z [M]., n

A etone e t act 0.220 +0. 100 +45.4 +3s.1 0.114 +0055 +4s.2 +405 Etherextract 0.305 +0.a55 +97.3 +s1.7 0.207 +0.245 +11s +091 Benzene extract0.595 +0. 220 +36. 9 +30. 9 0. 108 +0. 040 +37. 0 +31. 1 Extractobtained after treatment in autoclave at 280 C. for 14 hours 0. 040 +0.035 +87. 5 +73. 5 Residue after treatment in autoclave, purified a bytreatment wth methanol and HCl as described in the example 0. 080 +0.090 +112 +94. 1 Residue after extraction practically insoluble indeca1in 0.017 +0.020 +117 +9s.3

1 The final purification was carried out by prolonged boiling of thepolymer under nitrogen first with cone. H01 and then with methanol, inorder to remove the acidity, and the residues were finally filtered,washed with methanol and dried by heating under vacuum.

2 The molar optical activity is referred to the molecular weight of onemonomeric unit.

The optically active and the inactive poly-3-methylpentene-l, finallypurified as described have the following melting points (determined in acapillary):

were measured. The data related to the extraction with ether and acetoneare reported in Table IV.

Table IV poly-3-methyl-pentene-1, obtained from the active olefin,melting point 277 C. Fractions G. Percent [1 poly-3-methyl-pentene-1;obtained from the racemic olefin, melting point 268 C. Acetone extract0.071 11.3

Ether extract 0.388 61.8 1 awe-3.1

The X-rays examination of the two pulverized poly- Residue (by(inference) 169 mers showed that the optically active polymer had a 10Purfied po ymer subjected to much higher crystallinity than the racemicpolymer. ex we 100") 1 In 13 t 20 0. EXAMPLE 2 2 In te t r llgdionaphythalene at 120 1.44 g. of (S)-3-n1ethyl-pentene-1, having an 15Table V reports the measured rotation angles and the optical purity ofat least 90% and an n =l.3845, were specific and molar rotatory powerscalculated therefrom sealed in a glass vial together with 0.197 g. TiCland for the various fractions shown in Table IV. 0.676 g. distilledAl(i-C H Table V The polymerization proceeded rapidly at roomtemperature and after about 1 hour no liquid was left in the FractionsG./100m1. a el b l- Solvent vial.

The obtained product was purified by means of sucgg 8332 +ggg +50%:gegzene. cessive treatments under nitrogen with an ethereal hy- 5 3221:1 1 0 1 0 9 0 g ig' drochloric acrd solution and with methanol. Thepunfied polymer weighed 0.862 g.; further 0.043 g. of polymer 5 Themelting point of the residue was found to he were obtained byevaporating the solvents. used in the higher than 178 C. a purificationsteps. The optically active polymer, obtained as a residue Table IIIshows the optical activity and the specific after the extraction,exhibits, on X-ray examination, a rotation referred to the monomericunit, of the fraction crystallinity which is much higher than that ofthe racemic obtained by extracting the crude polymer with different 6poly-methyl-hexene-l having about the same melting solvents. point.

Table III Fractions Percent G./100 ml. a [04] in oflHt Acetoneextract 1. 5 0.118 +0.065 at 20 0. (1:1) +55 Ether extract 1.8 0. 200+0.3e5 at 20 0 (1:1) +12e Iso-octane extract 1. 6 0.058 +0.260 at 60 0(1 4) +112 Residue 95.1 Not dot.

2.40 g. racemic 3-methyl-pentene-1, having an EXAMPLE 4 2.79 g. racemic4-methyl-hexene-l, having n =13845 n =l.40O2 were sealed in a glass vialtogether w1th 0.325 g. T1Cl and 1.126 g Previously distilled A1(i C4H9)3were sealed 1n a glass v1al together with 0.12 g. T1Cl and Thepolymerization proceeded rapidly at room temof Previously dlstllled Yperature and after 2 hours no liquid was any longer obbutyl] alumlnumethelate ([]D O served in the vial. The latter was then opened and the-The V131 was kept at room temperature (about 18 obtained product waspurified by successive treatments, for 7 days and was thoen heated f Patfhe under nitroggn, with ethereal Solutions of Hcl and averagetemperature of 90 C. After th1s penod'of time CHSOH the Vial was openedand the polymer was purified by pro- The Polymer Comprising also theoily fract'ions longed boiling under nitrogen, with methanol and cone.solved in the solvents used in the purification step and hydrochloilcacldrecovered therefrom by evaporation and extraction with p t p m thusQbtamed wefghed benzene, weighed 104 Said oily fractions together Itsfract1onat1on w1th ether and acetone m a Kumagawa with the acetonicextract determined by extracting the extractor gave/F116 resultsreported m Table purified polymer in a Kumagawa extractor, corre- TableVI sponded to 18. 1% of the weight of the obtained polymer.

1.4 g. of (S)-4-methyl-hexene-1, having an optical ff purity of about90%, n =1. l003, and [a] 2.52, v were closed in a glass vial togetherwith 0.15 g. TiCl Acetoneextract 0.151 21.0 and 0.58 g. previouslydistilled triisobutyl-aluminum. gfi gggg ig'fifi' g i 31 28:?

The olefin Was polymerized at about 20 C. for 4 Purified polymeiSub,ected to days and thereafter the vial was opened and the polymertraction 0.691 100.0 was purified by protracted boiling with methanoland Hcl Pnder mtmgen' The acetone extract showed, in benzene Thepurlfied polymer thus obtalned welghed 0.67 g. n o

It was then fractionated in a Kumagawa extractor and [M19 the opticalactivities of the various fractions obtained (referred to the weight ofthe monomeric unit) and the I 97.4%) with thionyl-chloride.

gram-atoms) of Mg'suspended inanhydrous ether weretreated under nitrogenwith 266g. (2.5 mob). of (S)- I-chlOIo-Z-methyl-butane, in ethersolution, having (optical purity 96.3% obtained by reacting (S)-2-methyl-butanol, having [a] .75

After starting the reaction by, means of a short heating at hightemperature and the introduction of a smalliodine crystal, theintroduction of the alkyl chloride was regulated to maintain a constantslow reflux. 1 The final volume was of about 950 ml. The'reaction wascompleted by protracting the agitation for 2 hours. 75.5 g. (0.566 mols)of AlCl dissolved in' anhydrous ether, were thus introduced into the'fiask. The addition (optical purity cal purity of at least 91%., and0.55 g. of titanium tetra-, 7

J f is bubbled through a mixture of 5.67-g. of the etherateof -trisr-'[(S)-2 methyl-butyl] aluminum having an opti-.

chloride contained in a test'tub'e.

The tube is heated slowly up to 80 Ciand kept at this temperature for 9/2 hours, during which time propylene is bubbled through'continuously,at the rate of approximately 1 liter per hour.

At the end of this time the rnetallorganic compounds present in thereaction productare slowly decomposed under nitrogenbymeans of methanol,and the polymer of the AlCl ether solution to the Grignard compound wasthe agitation was continued for one hour. a

From the ether'solution, containing the (+)-tris- [(S)-2-methyl-butyl]aluminum etherate, the ether was evaporated under reduced pressure, (theremaining traces were eliminated by slightly heating thev reactionflask) petroleum ether, free of olefins (boiling point 40'-50 C.),distilled under nitrogen on sodium, was then added under stirring. Afterdecantation, the clear layer was 'siphonedunder pure dry nitrogen. Thisoperation was repeated 5 times, the extracts were combined, thepetroleum ether was distilled ofif almost completely by distillationunder N at the lowest possible temperature, and the last traces of thepetroleum ether were then removed under'reduced pressure.

The crude product yielded. by vacuum distillation, the

treatments with methanol and traded with boiling solvents in a Kumagawaextractor.

The acetone extract (14.4% of the total) dissolved in benzene shows aspecificro'tation [a] =3.9; the ether extract (11.4%) a specificrotation [d] =-|-l.9.

The present polymerization process can be carried out at temperatures inthe range from 0 to 100 C.

In the examples illustrating our invention applied to. thepolymerization of optically active .alpha-olefins, the catalyst used wasobtained by mixing TiCl respectively TiCl with Al (isobutyl) It willbeunderstood that other catalysts prepared by mixing a transition metalhalide with an organometallic compound can be used.

Preferred catalysts are those obtained by mixing halides of transitionmetals Ti, V, or Zr, with alkyl compounds of Li, Be, Mg or Al in whichthe alkyl radicals contain 2 to 8 carbon atoms, or with monohalides ofdialkyl Al,

e.g., chlorides or bromides of dialkyl Al in which the alkyl radicalscontain 2 to. 8 carbon atoms. g Specific catalyst-component combinationsare: TiCl (or TiCl or TiCl with triethy'l- '(or tri-isobutyl)Al or withdiethyl Al monochloride; VCl (or VCLQ with triethyl Al or diethyl Almonochloride, and similar com- -tris- (S) -2-methyl-butyl] -aluminumetherafe having 0.26 g. of previously distilled triisobutylaluminum. The

polymerization was continued for 19 days. During that period, the vialwas heated for 69 hours at an average temperature of C. The vial wasthen opened and the polymer was purified by prolonged boiling undernitrogen with methanol and cone. hydrochloricacid.

After this treatment, 0.82 g. polymer were obtained,f

and then subjected to solvent extraction in a'Kumagawa extractor.

The polymer appeared to consist of 33% oily low molecular weightfractions soluble in acetone; the residue bina-tions of ZrCl or ZrCl 1Various changes in details maybe made'in practicing the invention, suchas variations in the starting monomer,

the catalyst used, and the solvents used for effecting the the scope ofthe appended claims all'such modifications as may be apparent to thoseskilled in the art from the description and examples of our invention asdisclosed here- What is claimed is:

V 1. Normally solid homopolymers of alpha-olefins having the generalformula V CH CHR where R is selected from the group consisting ofbranched alkyl radicals containing from 4 to 8 carbon atoms at least oneof which is an asymmetric carbon atom, and

was crystalline and completely soluble in ether. -Ta'ble.

VII shows the measured rotation angles and the values of specific andmolar rotation calculated therefrom, for

the acetone extract and for the residue soluble in ether.

7 Table VII Fractions (1241100 [(1199 (1-2) [ak [M]D1 Solvent 7 Acetoneextract. 1.l54 7 +0. 27 +11. 7 4-13.1 Benzene. Residue 0.602 +0. 71 +59.0 +66.1 Do.

EXAMPLE 6' Dry propylene, under a pressure of one atmosphere,

alkylaryl radicals in whichthe alkyl portion contains from 2 to 8 carbonatoms at least one of which is an asymmetric carbon atom, saidhomopolymer being characterized in consisting prevailingly of isotacticmacromolecules and in exhibiting optical activity in solution.

2. A normally solid homopolymer of (S)-3-methyl-pentene-l, saidhomopolymer being characterized in exhibiting optical activity insolution.

3. A normally solid polymer of ()(S)-,4-methyl- :hexene-l, characterizedin consisting prevailingly of isotactic'macromolecules and in exhibitingoptical activity 4. A normally solid polymer of (S)-5-methylheptene-lcharacterized. in consisting prevailingly of isotactic macromoleculesand in exhibiting'optical activity in solution.

5. A process for producing homopolymerizates which exhibit opticalactivity in solution, from optically active alpha-olefins of the formulaCH CHR in which R is selected from the group consisting of branchedaliphatic radicals containing from 4 to 8 carbon atoms at least one ofwhich is an asymmetric carbon atom, and alkylaryl radicals in which thealkyl portion contains from 1 to 8 carbon atoms at least one of which isan asymmetric carbon atom, which process comprises polymerizing saidalpha-olefin in contact with a catalyst consisting essentially of theproduct obtained by mixing a halide of a transition metal selected fromthe group consisting of Ti, V and Zr with a substance selected from thegroup consisting of fully alkylated derivatives of Li, Be, Mg and Al,and dialkyl Al monohalides, and in which the alkyl groups contain from 2to 8 carbon atoms organometallic compound of an element belonging toGroups I to III inclusive of said table.

6. The process according to claim 5, characterized in that the catalystis obtained by starting with TiCl and mixing the TiCl with trialkylaluminum.

7. The process according to claim 4, characterized in that the catalystis obtained by starting with TiCl and mixing the TiCl with trialkylaluminum.

8. The process according to claim 4, characterized in that the opticallyactive alpha-olefin is (S)-3-methylpentene-l.

9. The process according to claim 4, characterized in that the opticallyactive alpha-olefin is (S)-4-methylhexene-l.

10. The process according to claim 5, characterized in that theoptically active alpha-olefin is (S)-5-methylheptene-l.

11. A process for producing homopolymerizates which exhibit opticalactivity in solution from optically inactive alpha-olefins of theformula CH =CHR in which R is selected from the group consisting ofalkyl radicals containing from 1 to 8 carbon atoms, the phenyl radical,and

the phenyl radical substituted by alkyl groups containing from 1 to 8carbon atoms, which process comprises polymerizing the alpha-olefin incontact with a catalyst consisting essentally of the product obtained bymixing a halide of a transition metal selected from the group consistingof Ti, V and Zr with an optically active organo metallic compound havingthe formula MeR'n References Cited by the Examine" FOREIGN PATENTS 5/55Italy. 7/56 Italy.

OTHER REFERENCES Gaylord et al., Linear and Stereoregular AdditionPolymers (1959), pages 40-44, Interscience Publishers Inc., New York.

Gaylord et al., Linear and Stereoregular Addition Polymers, IntersciencePublishers Inc., New York, pages 133 and 220.

Arcus, J. Chem. Soc., 1957, pages 1189-96, pages 1194- 96 only needed.

Beredjick et al., J. Am. Chem. Soc., vol. 80, pages 1933- 38 1958 JOSEPHL. SCHOFER, Primary Examiner.

LESLIE H. GASTON, WILLIAM H. SHORT,

Examiners.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No.3,193,544 July 6, 1965 Giulio Natta et al.

It is hereby certified that error appears in the above numbered patentrequiring correction and that the said Letters Patent should read ascorrected below.

Column 1, line 11, for "process" read processes line 63, for "rotary"read rotatory column 3, line 30,

n n for 3.38 g. Al(1-C H read 3.38 g. Al(1 C H line 3 f 1'- H T' 6, orAl(1 C H /T1Cl read A (1 C 1C1 columns 3 and 4, Table II, sub-heading tothe third column, for

25 '27 D' read ll l=l l'=l column 8, lines 68 and 72, for "polymer",each occurrence,- read homopolymer column 9, lines 18 to 20", 'strikeout "-organometallic compound of arr-element belonging to Groups I toI11 inclusive of said table".

Signed and sealed this 16th day of August 1966.

(SEAL) Attest:

ERNEST W. SWIDER EDWARD J. BRENNER Attesting Officer Commissioner ofPatents

1. NORMALLY SOLID HOMOPOLYMERS OF ALPHA-OLEFINS HAVING THE GENERALFORMULA